Fluorescent carbon dots are the new quantum dots: an overview of their potential in emerging technologies and nanosafety
Source abstract
Abstract
Carbon dots (CDs) have become a potential material for biosensing, drug delivery, and bioimaging because of their strong fluorescence, for which they are referred to as fluorescent carbon dots. CDs have drawn significant attention as a new class of carbonaceous nanomaterials with accelerating applications in varying different technologies. This attention is mainly based on a multitude of appealing properties of CDs, such as high hydrophilicity, biodegradability, biocompatibility, chemical stability, and ease of surface modification, together with their unique optic properties. In this review, CDs were classified and evaluated based on the difference in precursors and preparation methods. The synthetic methods of CDs were summarized, and their luminescence mechanism was analyzed. The applications of CDs in biosensing, drug delivery, energy, and bioimaging were also discussed. The issues and challenges of CDs were analyzed for their further development, with specific emphasis on the toxicity profiles or lack thereof, especially that of cytotoxicity and long-term genotoxicity developed secondary to nanotoxic effects, of carbon dot-based systems. Additional research in toxicity is sure to lead to improved baseline nanosafety statistics for CDs and will be a crucial determinant in the adoption of CDs into many fields across all scientific disciplines, as well as indirectly assist in the development of more efficient and cost-effective technologies. Suggestions for the development of the concepts contemplated herein were also provided, along with additional insight into the controversy concerning the phenomenon of emission and the upconverted photoluminescence.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Carbon and Quantum Dots Applications · Nanocluster Synthesis and Applications · Heavy Metal Exposure and Toxicity
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (100+)
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1. Yan F, Zhang H, Sun Z et al (2019) Carbon dots as building blocks for the construction of functional nanocomposite materials. J Iran Chem Soc 17:1–15. https://doi.org/10.1007/s13738-019-01749-510.1007/s13738-019-01749-5 ↗
2. Murugan AV, Kumar Y, Periyasamy L, Santhakumar M (2018) Transition metal ion (Mn2+, Fe2+, Co2+, and Ni2+)-doped carbon dots synthesized via microwave-assisted pyrolysis: a potential nanoprobe for magneto-fluorescent dual-modality bioimaging. ACS Biomater Sci Eng 4:2582–2596. https://doi.org/10.1021/acsbiomaterials.7b0094310.1021/acsbiomaterials.7b00943 ↗
3. Li H, Kang Z, Liu Y, Lee S-T (2012) Carbon nanodots: synthesis, properties and applications. J Mater Chem 22:24230–24253. https://doi.org/10.1039/c2jm34690g10.1039/c2jm34690g ↗
4. Jeong CJ, Roy AK, Kim SH et al (2014) Fluorescent carbon nanoparticles derived from natural materials of mango fruit for bio-imaging probes. Nanoscale 6:15196–15202. https://doi.org/10.1039/C4NR04805A10.1039/C4NR04805A ↗
5. Wang L, Li B, Xu F et al (2016) High-yield synthesis of strong photoluminescent N-doped carbon nanodots derived from hydrosoluble chitosan for mercury ion sensing via smartphone APP. Biosens Bioelectron 79:1–8. https://doi.org/10.1016/j.bios.2015.11.08510.1016/j.bios.2015.11.085 ↗
6. Guo X, Wang C-F, Yu Z-Y et al (2012) Facile access to versatile fluorescent carbon dots toward light-emitting diodes. Chem Commun 48:2692–2694. https://doi.org/10.1039/c2cc17769b10.1039/c2cc17769b ↗
7. Ming H, Ma Z, Liu Y et al (2012) Large scale electrochemical synthesis of high quality carbon nanodots and their photocatalytic property. Dalton Trans 41:9526–9531. https://doi.org/10.1039/c2dt30985h10.1039/c2dt30985h ↗
8. Xu X, Ray R, Gu Y et al (2004) Electrophoretic analysis and purification of fluorescent single-walled carbon nanotube fragments. J Am Chem Soc 126:12736–12737. https://doi.org/10.1021/ja040082h10.1021/ja040082h ↗
9. Sciortino A, Cannizzo A, Messina F (2018) Carbon nanodots: a review—from the current understanding of the fundamental photophysics to the full control of the optical response. J Carbon Res 4:67–102. https://doi.org/10.3390/c404006710.3390/c4040067 ↗
10. Bhattacharya D, Mishra MK, De G (2017) Carbon dots from a single source exhibiting tunable luminescent colors through the modification of surface functional groups in ORMOSIL films. J Phys Chem C 121:28106–28116. https://doi.org/10.1021/acs.jpcc.7b0803910.1021/acs.jpcc.7b08039 ↗
11. Barman MK, Patra A (2018) Current status and prospects on chemical structure driven photoluminescence behaviour of carbon dots. J Photochem Photobiol C Photochem Rev 37:1–22. https://doi.org/10.1016/j.jphotochemrev.2018.08.00110.1016/j.jphotochemrev.2018.08.001 ↗
12. Sun YP, Zhou B, Lin Y et al (2006) Quantum-sized carbon dots for bright and colorful photoluminescence. J Am Chem Soc 128:7756–7757. https://doi.org/10.1021/ja062677d10.1021/ja062677d ↗
13. Bourlinos AB, Stassinopoulos A, Anglos D et al (2008) Photoluminescent carbogenic dots. Chem Mater 20:4539–4541. https://doi.org/10.1021/cm800506r10.1021/cm800506r ↗
14. Liu H, Ye T, Mao C (2007) Fluorescent carbon nanoparticles derived from candle soot. Angew Chem 119:6473–6475. https://doi.org/10.1002/anie.20070127110.1002/anie.200701271 ↗
15. Liu R, Wu D, Liu S et al (2009) An aqueous route to multicolor photoluminescent carbon dots using silica spheres as carriers. Angew Chem Int Ed 48:4598–4601. https://doi.org/10.1002/anie.20090065210.1002/anie.200900652 ↗
16. Zhu H, Wang X, Li Y et al (2009) Microwave synthesis of fluorescent carbon nanoparticles with electrochemiluminescence properties. Chem Commun 34:5118–5120. https://doi.org/10.1039/b907612c10.1039/b907612c ↗
17. Chan WCW, Maxwell DJ, Gao X et al (2002) Luminescent quantum dots for multiplexed biological detection and imaging. Curr Opin Biotechnol 13:40–46. https://doi.org/10.1016/S0958-1669(02)00282-310.1016/S0958-1669(02)00282-3 ↗
18. Gibbs SL (2012) Near infrared fluorescence for image-guided surgery. Quant Imaging Med Surg 2:177–187. https://doi.org/10.3978/j.issn.2223-4292.2012.09.0410.3978/j.issn.2223-4292.2012.09.04 ↗
19. Yang S-T, Cao L, Luo PG et al (2009) Carbon dots for optical imaging in vivo. J Am Chem Soc 131:11308–11309. https://doi.org/10.1021/ja904843x10.1021/ja904843x ↗
20. Lim MC, Seo S-S, Kang S et al (2012) Intraoperative image-guided surgery for ovarian cancer. Quant Imaging Med Surg 2:114–117. https://doi.org/10.3978/j.issn.2223-4292.2012.06.0110.3978/j.issn.2223-4292.2012.06.01 ↗
21. Dong Y, Wang R, Li G et al (2012) Polyamine-functionalized carbon quantum dots as fluorescent probes for selective and sensitive detection of copper ions. Anal Chem 84:6220–6224. https://doi.org/10.1021/ac301212610.1021/ac3012126 ↗
22. Li Y, Hu Y, Zhao Y et al (2011) An electrochemical avenue to green-luminescent graphene quantum dots as potential electron-acceptors for photovoltaics. Adv Mater 23:776–780. https://doi.org/10.1002/adma.20100381910.1002/adma.201003819 ↗
23. Lee JH, Park G, Hong GH et al (2012) Design considerations for targeted optical contrast agents. Quant Imaging Med Surg 2:266–273. https://doi.org/10.3978/j.issn.2223-4292.2012.12.0410.3978/j.issn.2223-4292.2012.12.04 ↗
24. Gao X, Yang L, Petros JA et al (2005) In vivo molecular and cellular imaging with quantum dots. Curr Opin Biotechnol 16:63–72. https://doi.org/10.1016/j.copbio.2004.11.00310.1016/j.copbio.2004.11.003 ↗
25. Statement PE (2013) Quantitative imaging in medicine and surgery: progress & perspective. Quant Imaging Med Surg 3:1–4. https://doi.org/10.3978/j.issn.2223-4292.2013.02.0810.3978/j.issn.2223-4292.2013.02.08 ↗
26. Lim SY, Shen W, Gao Z (2015) Carbon quantum dots and their applications. Chem Soc Rev 44:362–381. https://doi.org/10.1039/C4CS00269E10.1039/C4CS00269E ↗
27. Yang Y, Cui J, Zheng M et al (2012) One-step synthesis of amino-functionalized fluorescent carbon nanoparticles by hydrothermal carbonization of chitosan. Chem Commun 48:380–382. https://doi.org/10.1039/C1CC15678K10.1039/C1CC15678K ↗
28. Du F, Zhang M, Li X et al (2014) Economical and green synthesis of bagasse-derived fluorescent carbon dots for biomedical applications. Nanotechnology 25:315702. https://doi.org/10.1088/0957-4484/25/31/31570210.1088/0957-4484/25/31/315702 ↗
29. Jaiswal A, Ghosh SS, Chattopadhyay A (2012) One step synthesis of C-dots by microwave mediated caramelization of poly(ethylene glycol). Chem Commun 48:407–409. https://doi.org/10.1039/C1CC15988G10.1039/C1CC15988G ↗
30. Sk MP, Jaiswal A, Paul A et al (2012) Presence of amorphous carbon nanoparticles in food caramels. Sci Rep 2:1–5. https://doi.org/10.1038/srep0038310.1038/srep00383 ↗
31. Park SY, Lee HU, Park ES et al (2014) Photoluminescent green carbon nanodots from food-waste-derived sources: large-scale synthesis, properties, and biomedical applications. ACS Appl Mater Interfaces 6:3365–3370. https://doi.org/10.1021/am500159p10.1021/am500159p ↗
32. Lu W, Qin X, Liu S et al (2012) Economical, green synthesis of fluorescent carbon nanoparticles and their use as probes for sensitive and selective detection of mercury(II) ions. Anal Chem 84:5351–5357. https://doi.org/10.1021/ac300793910.1021/ac3007939 ↗
33. Das B, Dadhich P, Pal P et al (2014) Carbon nanodots from date molasses: new nanolights for the in vitro scavenging of reactive oxygen species. J Mater Chem B 2:6839–6847. https://doi.org/10.1039/C4TB01020E10.1039/C4TB01020E ↗
34. Ke Y, Garg B, Ling Y (2014) Waste chicken eggshell as low-cost precursor for efficient synthesis of nitrogen-doped fluorescent carbon nanodots and their multi-functional applications. RSC Adv 4:58329–58336. https://doi.org/10.1039/C4RA10178B10.1039/C4RA10178B ↗
35. Liu S-S, Wang C-F, Li C-X et al (2014) Hair-derived carbon dots toward versatile multidimensional fluorescent materials. J Mater Chem C 2:6477–6483. https://doi.org/10.1039/C4TC00636D10.1039/C4TC00636D ↗
36. Chandra S, Das P, Bag S et al (2011) Synthesis, functionalization and bioimaging applications of highly fluorescent carbon nanoparticles. Nanoscale 3:1533–1540. https://doi.org/10.1039/c0nr00735h10.1039/c0nr00735h ↗
37. Hu S-L, Niu K-Y, Sun J et al (2009) One-step synthesis of fluorescent carbon nanoparticles by laser irradiation. J Mater Chem 19:484–488. https://doi.org/10.1039/B812943F10.1039/B812943F ↗
38. Zhai X, Zhang P, Liu C et al (2012) Highly luminescent carbon nanodots by microwave-assisted pyrolysis. Chem Commun 48:7955–7957. https://doi.org/10.1039/c2cc33869f10.1039/c2cc33869f ↗
39. Zhang C, Hu Z, Song L et al (2015) Valine-derived carbon dots with colour-tunable fluorescence for the detection of Hg 2+ with high sensitivity and selectivity. New J Chem 39:6201–6206. https://doi.org/10.1039/C5NJ00554J10.1039/C5NJ00554J ↗
40. Jiang K, Sun S, Zhang L et al (2015) Red, green, and blue luminescence by carbon dots: full-color emission tuning and multicolor cellular imaging. Angew Chem Int Ed 54:5360–5363. https://doi.org/10.1002/anie.20150119310.1002/anie.201501193 ↗
41. Wang X, Cao L, Yang ST et al (2010) Bandgap-like strong fluorescence in functionalized carbon nanoparticles. Angew Chem Int Ed 49:5310–5314. https://doi.org/10.1002/anie.20100098210.1002/anie.201000982 ↗
42. Mehtaa VN, Jha S, Singhalc RK, Kailasaa SK (2014) Preparation of multicolor emitting carbon dots for HeLa cell imaging. New J Chem 38:6152–6160. https://doi.org/10.1039/C4NJ00840E.This10.1039/C4NJ00840E.This ↗
43. Gupta A, Verma NC, Khan S et al (2016) Paper strip based and live cell ultrasensitive lead sensor using carbon dots synthesized from biological media. Sens Actuators B Chem 232:107–114. https://doi.org/10.1016/j.snb.2016.03.11010.1016/j.snb.2016.03.110 ↗
44. Sahu S, Behera B, Maiti TK, Mohapatra S (2012) Simple one-step synthesis of highly luminescent carbon dots from orange juice: application as excellent bio-imaging agents. Chem Commun 48:8835–8837. https://doi.org/10.1039/c2cc33796g10.1039/c2cc33796g ↗
45. Li L, Dong T (2018) Photoluminescence tuning in carbon dots: surface passivation or/and functionalization, heteroatom doping. J Mater Chem C 6:7944–7970. https://doi.org/10.1039/c7tc05878k10.1039/c7tc05878k ↗
46. Simsek S, Alas MO, Ozbek B, Genc R (2019) Fluorescent carbon dots from Nerium oleander: effects of physical conditions and the extract types. J Fluoresc 29:853–86410.1007/s10895-019-02390-4 ↗
47. Sharma V, Tiwari P, Mobin SM (2017) Sustainable carbon-dots: recent advances in green carbon dots for sensing and bioimaging. J Mater Chem B 5:8904–8924. https://doi.org/10.1039/c7tb02484c10.1039/c7tb02484c ↗
48. Alas MO, Genc R (2017) An investigation into the role of macromolecules of different polarity as passivating agent on the physical, chemical and structural properties of fluorescent carbon nanodots. J Nanoparticle Res 19:185–199. https://doi.org/10.1007/s11051-017-3863-110.1007/s11051-017-3863-1 ↗
49. Shen J, Zhu Y, Yang X, Li C (2012) Graphene quantum dots: emergent nanolights for bioimaging, sensors, catalysis and photovoltaic devices. Chem Commun 48:3686–3699. https://doi.org/10.1039/c2cc00110a10.1039/c2cc00110a ↗
50. Zhang H, Chen Y, Liang M et al (2014) Solid-phase synthesis of highly fluorescent nitrogen-doped carbon dots for sensitive and selective probing ferric ions in living cells. Anal Chem 86:9846–9852. https://doi.org/10.1021/ac502446m10.1021/ac502446m ↗
51. Cao L, Wang X, Meziani MJ et al (2007) Carbon dots for multiphoton bioimaging. J Am Chem Soc 129:11318–11319. https://doi.org/10.1021/ja073527l10.1021/ja073527l ↗
52. Mukherjee P, Misra SK, Gryka MC et al (2015) Tunable luminescent carbon nanospheres with well-defined nanoscale chemistry for synchronized imaging and therapy. Small 11:4691–4703. https://doi.org/10.1002/smll.20150072810.1002/smll.201500728 ↗
53. Bourlinos AB, Stassinopoulos A, Anglos D et al (2008) Surface functionalized carbogenic quantum dots. Small 4:455–458. https://doi.org/10.1002/smll.20070057810.1002/smll.200700578 ↗
54. Ray SC, Saha A, Jana NR, Sarkar R (2009) Fluorescent carbon nanoparticles: synthesis, characterization, and bioimaging application. J Phys Chem C 113:18546–18551. https://doi.org/10.1021/jp905912n10.1021/jp905912n ↗
55. Genc R, Alas MO, Harputlu E et al (2017) High-capacitance hybrid supercapacitor based on multi-colored fluorescent carbon-dots. Sci Rep 7:11222. https://doi.org/10.1038/s41598-017-11347-110.1038/s41598-017-11347-1 ↗
56. Alas MO, Güngör A, Genc R, Erdem E (2019) Feeling the power: robust supercapacitor from nanostructured conductive polymer fostered with Mn2+ and carbon dots. Nanoscale 11:12804–12816. https://doi.org/10.1039/C9NR03544C10.1039/C9NR03544C ↗
57. Gayen B, Palchoudhury S, Chowdhury J (2019) Carbon dots: a mystic star in the world of nanoscience. J Nanomater. https://doi.org/10.1155/2019/345130710.1155/2019/3451307 ↗
58. Emam AN, Loutfy SA, Mostafa AA et al (2017) Cyto-toxicity, biocompatibility and cellular response of carbon dots-plasmonic based nano-hybrids for bioimaging. RSC Adv 7:23502–23514. https://doi.org/10.1039/c7ra01423f10.1039/c7ra01423f ↗
59. Baker SN, Baker GA (2010) Luminescent carbon nanodots: emergent nanolights. Angew Chem Int Ed 49:6726–6744. https://doi.org/10.1002/anie.20090662310.1002/anie.200906623 ↗
60. Tang L, Ji R, Cao X et al (2012) Deep ultraviolet photoluminescence graphene quantum dots. ACS Nano 6:5102–5110. https://doi.org/10.1021/nn300760g10.1021/nn300760g ↗
61. Mochalin VN, Gogotsi Y (2009) Wet chemistry route to hydrophobic blue fluorescent nanodiamond. J Am Chem Soc 131:4594–4595. https://doi.org/10.1021/ja900451410.1021/ja9004514 ↗
62. Yan F, Sun Z, Zhang H et al (2019) The fluorescence mechanism of carbon dots, and methods for tuning their emission color: a review. Microchim Acta 186:583. https://doi.org/10.1007/s00604-019-3688-y10.1007/s00604-019-3688-y ↗
63. Sun D, Ban R, Zhang PH et al (2013) Hair fiber as a precursor for synthesizing of sulfur- and nitrogen-co-doped carbon dots with tunable luminescence properties. Carbon N Y 64:424–434. https://doi.org/10.1016/j.carbon.2013.07.09510.1016/j.carbon.2013.07.095 ↗
64. Cui Y, Zhang C, Sun L et al (2015) Simple and efficient synthesis of strongly green fluorescent carbon dots with upconversion property for direct cell imaging. Part Part Syst Charact 32:542–546. https://doi.org/10.1002/ppsc.20140022110.1002/ppsc.201400221 ↗
65. Wu Z, Song T, Sun B (2017) Carbon-based materials used for perovskite solar cells. ChemNanoMat 3:75–88. https://doi.org/10.1002/cnma.20160031210.1002/cnma.201600312 ↗
66. Fagiolari L, Bella F (2019) Carbon-based materials for stable, cheaper and large-scale processable perovskite solar cells. Energy Environ Sci 12:3437–3472. https://doi.org/10.1039/c9ee02115a10.1039/c9ee02115a ↗
67. Fu X, Xu L, Li J et al (2018) Flexible solar cells based on carbon nanomaterials. Carbon N Y 139:1063–1073. https://doi.org/10.1016/j.carbon.2018.08.01710.1016/j.carbon.2018.08.017 ↗
68. Jin J, Chen C, Li H et al (2017) Enhanced performance and photostability of perovskite solar cells by introduction of fluorescent carbon dots. ACS Appl Mater Interfaces 9:14518–14524. https://doi.org/10.1021/acsami.7b0224210.1021/acsami.7b02242 ↗
69. Zhu X, Sun J, Yuan S et al (2019) Efficient and stable planar perovskite solar cells with carbon quantum dots-doped PCBM electron transport layer. New J Chem 43:7130–7135. https://doi.org/10.1039/c8nj06146g10.1039/c8nj06146g ↗
70. Molaei MJ (2020) The optical properties and solar energy conversion applications of carbon quantum dots: a review. Sol Energy 196:549–566. https://doi.org/10.1016/j.solener.2019.12.03610.1016/j.solener.2019.12.036 ↗
71. Guo X, Zhang H, Sun H et al (2017) Green synthesis of carbon quantum dots for sensitized solar cells. ChemPhotoChem 1:116–119. https://doi.org/10.1002/cptc.20160003810.1002/cptc.201600038 ↗
72. Wang S, Zhu Y, Liu B et al (2019) Introduction of carbon nanodots into SnO2 electron transport layer for efficient and UV stable planar perovskite solar cells. J Mater Chem A 7:5353–5362. https://doi.org/10.1039/c8ta11651b10.1039/c8ta11651b ↗
73. Dao VD, Kim P, Baek S et al (2016) Facile synthesis of carbon dot-Au nanoraspberries and their application as high-performance counter electrodes in quantum dot-sensitized solar cells. Carbon N Y 96:139–144. https://doi.org/10.1016/j.carbon.2015.09.02310.1016/j.carbon.2015.09.023 ↗
74. Wang Y, Yan L, Ji G et al (2018) Synthesis of N, S-doped carbon quantum dots for use in organic solar cells as the ZnO modifier to eliminate the light-soaking effect. ACS Appl Mater Interfaces 11:2243–2253. https://doi.org/10.1021/acsami.8b1712810.1021/acsami.8b17128 ↗
75. Ma Z, Zhang YL, Wang L et al (2013) Bioinspired photoelectric conversion system based on carbon-quantum-dot- doped dye-semiconductor complex. ACS Appl Mater Interfaces 5:5080–5084. https://doi.org/10.1021/am400930h10.1021/am400930h ↗
76. Mirtchev P, Henderson EJ, Soheilnia N et al (2012) Solution phase synthesis of carbon quantum dots as sensitizers for nanocrystalline TiO2 solar cells. J Mater Chem 22:1265–1269. https://doi.org/10.1039/c1jm14112k10.1039/c1jm14112k ↗
77. Zhang YQ, Ma DK, Zhang YG et al (2013) N-doped carbon quantum dots for TiO2-based photocatalysts and dye-sensitized solar cells. Nano Energy 2:545–552. https://doi.org/10.1016/j.nanoen.2013.07.01010.1016/j.nanoen.2013.07.010 ↗
78. Zhu W, Duan J, Duan Y et al (2017) Efficiency enhancement of hybridized solar cells through co-sensitization and fast charge extraction by up-converted polyethylene glycol modified carbon quantum dots. J Power Sources 367:158–166. https://doi.org/10.1016/j.jpowsour.2017.09.05510.1016/j.jpowsour.2017.09.055 ↗
79. Zhang H, Zhang Q, Li M et al (2015) Investigation of the enhanced performance and lifetime of organic solar cells using solution-processed carbon dots as the electron transport layers. J Mater Chem C 3:12403–12409. https://doi.org/10.1039/c5tc02957k10.1039/c5tc02957k ↗
80. Zhang X, Li Z, Zhang Z et al (2016) Efficiency improvement of organic solar cells via introducing combined anode buffer layer to facilitate hole extraction. J Phys Chem C 120:13954–13962. https://doi.org/10.1021/acs.jpcc.6b0369710.1021/acs.jpcc.6b03697 ↗
81. Paulo S, Stoica G, Cambarau W et al (2016) Carbon quantum dots as new hole transport material for perovskite solar cells. Synth Met 222:17–22. https://doi.org/10.1016/j.synthmet.2016.04.02510.1016/j.synthmet.2016.04.025 ↗
82. Hui W, Yang Y, Xu Q et al (2019) Red-carbon-quantum-dot-doped SnO2 composite with enhanced electron mobility for efficient and stable perovskite solar cells. Adv Mater 1906374:1–9. https://doi.org/10.1002/adma.20190637410.1002/adma.201906374 ↗
83. Unnikrishnan B, Wu CW, Chen IWP et al (2016) Carbon dot-mediated synthesis of manganese oxide decorated graphene nanosheets for supercapacitor application. ACS Sustain Chem Eng 4:3008–3016. https://doi.org/10.1021/acssuschemeng.5b0170010.1021/acssuschemeng.5b01700 ↗
84. Hoang VC, Nguyen LH, Gomes VG (2019) High efficiency supercapacitor derived from biomass based carbon dots and reduced graphene oxide composite. J Electroanal Chem 832:87–96. https://doi.org/10.1016/j.jelechem.2018.10.05010.1016/j.jelechem.2018.10.050 ↗
85. Zhao X, Li M, Dong H et al (2017) Interconnected 3 D network of graphene-oxide nanosheets decorated with carbon dots for high-performance supercapacitors. Chemsuschem 10:2626–2634. https://doi.org/10.1002/cssc.20170047410.1002/cssc.201700474 ↗
86. Lv H, Gao X, Xu Q et al (2017) Carbon quantum dot-induced MnO2 nanowire formation and construction of a binder-free flexible membrane with excellent superhydrophilicity and enhanced supercapacitor performance. ACS Appl Mater Interfaces 9:40394–40403. https://doi.org/10.1021/acsami.7b1476110.1021/acsami.7b14761 ↗
87. Prasath A, Athika M, Duraisamy E et al (2018) Carbon-quantum-dot-derived nanostructured MnO2 and its symmetrical supercapacitor performances. ChemistrySelect 3:8713–8723. https://doi.org/10.1002/slct.20180195010.1002/slct.201801950 ↗
88. Wang Y, Zhu Y, Yu S, Jiang C (2017) Fluorescent carbon dots: rational synthesis, tunable optical properties and analytical applications. RSC Adv 7:40973–40989. https://doi.org/10.1039/c7ra07573a10.1039/c7ra07573a ↗
89. Wang H, Yang L, Chu S et al (2019) Semiquantitative visual detection of lead ions with a smartphone via a colorimetric paper-based analytical device. Anal Chem 91:9292–9299. https://doi.org/10.1021/acs.analchem.9b0229710.1021/acs.analchem.9b02297 ↗
90. Chu S, Wang H, Ling X et al (2020) A portable smartphone platform using a ratiometric fluorescent paper strip for visual quantitative sensing. ACS Appl Mater Interfaces 12:12962–12971. https://doi.org/10.1021/acsami.9b2045810.1021/acsami.9b20458 ↗
91. Wang Y, Zhang C, Chen X et al (2016) Ratiometric fluorescent paper sensor utilizing hybrid carbon dots-quantum dots for the visual determination of copper ions. Nanoscale 8:5977–5984. https://doi.org/10.1039/c6nr00430j10.1039/c6nr00430j ↗
92. Burcu BAÇ, Genç R (2017) Naked eye and smartphone applicable detection of toxic mercury ions using fluorescent carbon nanodots. Turk J Chem 41:931–943. https://doi.org/10.3906/kim-1701-4610.3906/kim-1701-46 ↗
93. Omer KM, Tofiq DI, Hassan AQ (2018) Solvothermal synthesis of phosphorus and nitrogen doped carbon quantum dots as a fluorescent probe for iron(III). Microchim Acta 185:4–11. https://doi.org/10.1007/s00604-018-3002-410.1007/s00604-018-3002-4 ↗
94. Jin H, Gui R, Wang Y, Sun J (2017) Carrot-derived carbon dots modified with polyethyleneimine and nile blue for ratiometric two-photon fluorescence turn-on sensing of sulfide anion in biological fluids. Talanta 169:141–148. https://doi.org/10.1016/j.talanta.2017.03.08310.1016/j.talanta.2017.03.083 ↗
95. Li P, Sun XY, Shen JS, Liu B (2016) A novel photoluminescence sensing system sensitive for and selective to bromate anions based on carbon dots. RSC Adv 6:61891–61896. https://doi.org/10.1039/c6ra12936f10.1039/c6ra12936f ↗
96. Baruah U, Gogoi N, Konwar A et al (2014) Carbon dot based sensing of dopamine and ascorbic acid. J Nanopart 2014:1–8. https://doi.org/10.1155/2014/17851810.1155/2014/178518 ↗
97. Hu X, Shi J, Shi Y et al (2019) Use of a smartphone for visual detection of melamine in milk based on Au@Carbon quantum dots nanocomposites. Food Chem 272:58–65. https://doi.org/10.1016/j.foodchem.2018.08.02110.1016/j.foodchem.2018.08.021 ↗
98. Wang L, Li M, Li W et al (2018) Rationally designed efficient dual-mode colorimetric/fluorescence sensor based on carbon dots for detection of pH and Cu2+ ions. ACS Sustain Chem Eng 6:12668–12674. https://doi.org/10.1021/acssuschemeng.8b0162510.1021/acssuschemeng.8b01625 ↗
99. Kumar P, Singh S, Gupta BK (2016) Future prospects of luminescent nanomaterials based security ink: from synthesis to anti-counterfeiting applications. Nanoscale 8:14297–14340. https://doi.org/10.1039/b000000x10.1039/b000000x ↗
100. Ganguly S, Das P, Banerjee S, Das NC (2019) Advancement in science and technology of carbon dot-polymer hybrid composites: a review. Funct Compos Struct 1:022001. https://doi.org/10.1088/2631-6331/ab0c8010.1088/2631-6331/ab0c80 ↗